But in recent years, the more than 20-year-old brand—the largest part of Booking Holdings, which also owns the likes of Priceline, Kayak, and OpenTable—has started to feel some serious heat from U.S. upstart Airbnb.

In April, Booking.com said that it had hit 5 million non-hotel listings, a figure that had grown 27% in the last year. Airbnb, meanwhile, is hot on its heels with 4.85 million listings.

Tans said that the company had started to see a growing interest in booking apartments and homes in its data, so it was already listing those kinds of properties when Airbnb emerged onto the scene. “We’ve always been an extremely customer-focused company,” she said at Fortune’s Most Powerful Women International summit in London on Monday.

She did note that Booking.com has “some catching up to do,” in the non-hotel segment in the U.S., where Airbnb is the leader.

Booking.com’s focus on being an “extremely data-driven company” is likely part of its strategy. Tans, who was an early employee of Booking.com and became CEO in 2016, said that machine learning is already heavily integrated into its process and that artificial intelligence has “enormous potential in travel.”

She noted that while more time is often spent planning a vacation than the length of the actual vacation itself, that AI has the “opportunity to make better choices for customers.”